Bed and cylinder printing mechanism with adjustable anvil



June 18, 1968 YOW-JIUN HU 3,338,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL Filed March10, 1965 5 Sheets-She et l .mvzmon Yow- J/un Hu ATTORNEY June 18, 1968YOW-JIUN HU 3,388,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL 5Sfieets-Sheet 2 Filed March 10, 1965 June 18, 1968 YOW-JIUN HU 3,388,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL Filed March10, 1965 5 Sheets-Sheet 5 United States Patent 3,388,659 BED ANDCYLINDER PRINTING MECHANISM WiTH ADJUSTABLE ANVIL Yow-Jiun Hu,Alexandria, Va., assignor to Farriugton Business Machines Corporation,Springfield, Va., a corporation of Massachusetts Filed Mar. 10, 1965,Ser. No. 433,-l85 2 Claims. (Cl. 101-269) ABSTRACT OF THE DISCLOSURE Anapparatus in a printing machine utilizing portable printing plates. Aprinting bed upon which the printing plate is seated to obtain optimumprinting pressure when the platen of the printing machine is pressedagainst a document overlying the printing plate. The printing bed is inthe form of an anvil and is adjusted to accommodate the particularprinting plate and/ or document thickness employed for a printingoperation. A sensing finger determines the thickness of the printingplate while seated on the anvil in accordance with the thickness thussensed. The sensing finger causes a spacer to be moved which spacerindirectly causes the anvil to be adjusted.

The present invention relates to a printing device and, moreparticularly, to an improved printing device for recording data on salesslip documents or the like by means of printing plates, having raisedtype characters thereon, of a kind suitable for use as identificationtokens and adapted to be carried by individual customers.

In printing devices of the variety disclosed above, it is well knownthat in order to obtain a uniform and clear imprint, the printingpressure should be maintained as much near a fixed value as possible. Inimprinters of the type where the shaft or other means carrying theplaten is constrained to reciprocating movement within a predeterminedpath, the upper portion of which defines a plane over the printing bedarea, a constant printing pressure reference gap will exist between theaforementioned plane and the printing bed surface. Such a printingpressure reference gap can readily be set to accommodate a printingplate and document of pre-estimated fixed thicknesses, by employingshimming techniques in the platen assembly or in the printing bed towiden or narrow the printing pressure reference gap for obtaining theproper printing pressure. However, it has been found that in actualpractice that printing plates and/ or sales slip documents having a widerange of thicknesses are utilized. Since mechanical limitations and thenecessity for expending considerable time make it quite impractical tomeasure thickness variances of the printing plate and/or document foreach transaction and accordingly shim the imprinter to adjust theprinting reference gap, the resultant printing pressure applied willvary to the extent that on many occurrences a uniform and clear imprintwill not be obtained.

The general purpose of this invention. is to provide an improvedprinting device which overcomes the aforeescribed disadvantages byautomatically providing a constant printing pressure for printing platesand/ or documents of varying thicknesses. To attain this, the presentinvention contemplates a unique anvil assembly which senses thethickness of the printing plate and/or document for each imprint cycleand automatically provides a related adjustment or compensation of theprinting reference gap in the printing device to produce an optimumprinting pressure.

An object of the present invention is the provision of a device whichproduces clean cut and uniform imprinting.

Another object of the present invention is to provide a Patented June18, 1968 substantially uniform printing pressure for printing platesand/ or documents of varying thicknesses.

A further object of the present invention is the provision of anautomatic device for sensing and compensating for varying printing plateand/ or document thicknesses to provide substantially uniform printingpressure.

Other objects, advantages, and capabilities of the present inventionwill become apparent from the following detailed description, taken inconjunction with the accompanying drawings, illustrating preferredembodiments of the invention.

In the drawings:

FIGURE 1 is a front perspeetvie view of an imprinter which may 'be usedwith the present invention.

FIGURE 2 is a perspective view of an embodiment of the presentinvention.

FIGURES 3 and 4 are cross-sectional views, taken on line 3-3 in FIGURE2, showing certain positions taken by the elements of the compensatingassembly as the printing device is operated.

FIGURE 5 is a cross-sectional view, taken on line 33 in FIGURE 2, butdisclosing a further manner of providing complementary surfaces betweenanvil 14 and wedge block 27.

FIGURE 6 is a perspective view of another embodiment of the presentinvention.

In FIGURE 1 there is shown an imprinter having a pair of C-frame members11 and 12, each being in parallel relationship with the other, yetspaced by a base member 13, there being located on the base member ananvil 14 which surface defines the plane of a printing bed. On

each side and parallel to the printing bed is located one of a pair ofguide rails 15 and 16, the guide rails being fastened at their ends tothe upper portion of the respective C-frame members by suitable means(not shown). The inner sides of the guide rails 15 and 16 are eachchanneled to define a pair of paths 17 and 18 respectively, for guidingthe bearings 19. The bearings are employed to guide a platen headassembly, generally referred to as 21, comprising a bracketed handle 20and platen 22 on shaft 23. The platen head assembly is directed over theanvil 14 for imprinting upon a document 24 disposed over the upwardlypresented face of a printing plate 25 hearing raised type charactersthereon, by exerting pressure on the same.

There is illustrated in FIGURES 2 and 3 the base 13 provided with acavity 26 wherein is seated a wedge block 27 and the anvil 14 overlyingthe wedge block. Wedge block 27, like anvil 14, is closely fitted in thecavity to prevent movement to the right or left as viewed along thelongitudinal axis of FIGURE 1; however, ample space is allowed for, sothat only the wedge block may slide on the cavity base in either of theopposite directions indicated by the numeral 28. Anvil 14 is thereforeso enclosed as to be restricted only to vertical movement in the cavity.The upper surface of wedge block 27 and the lower surface of anvil 14are so designed that each of the aforesaid surfaces is made to becomplementary with the other. Furthermore, each of the above-mentionedsurfaces is smoothly finished in a suitable manner to allow for minimumfriction and maximum sliding action between the two surfaces. The uppersurface of anvil 14- is adapted to support the printing plate 25, and atleast a portion of a document 24.

An L-like'shaped arm 29 is situated for pivotal movement about the pivotmember 31 which is fixedly attached to the base 13 and acts a areference piece. At one end of the arm 29 is a small elongated aperature32 for loosely receiving a rod 33 therein, the rod 33 being secured to aspacer 34 adapted for sliding vertical movement restricted by the guiderails 35 within a cut-out 35 located in the front side wall 37 of thebase 13. It is observed that the exterior 34' of spacer 34 is adapted tobe complementary with exterior 27 of wedge block 27 for flush engagementtherewith, whereby the exteriors are provided to have maximum frictionfor minimizing sliding with one another. At the remaining end of arm 29and integral therewith is a cross bar 38 each terminal portion of whichserves a separate purpose. The right hand terminal contains anadjustable sensor screw 39 having a flat-shaped lower end 41 overlying aportion of the document 24 and printing plate 25. The left hand terminalis provided with an angled bar 42 so positioned to engage either withthe platen roller 22, shaft 23, or some other portion of the platen readassembly 21 only when the platen head assembly lies in itsready-to-imprint position, as illustrated in FIGURE 1. A pair ofcompression springs 43 mounted on screws 44 are furnished to normallymaintain the wedge block 27 in a biased position toward the rear ofcavity 26.

In operation, assume that the imprinter being employed is of theunidirectional type, that is effecting an imprint when directed in onlyone direction such as that indicated by the arrow X in FIGURE 1. Whenthe platen roller 22 is returned to the left side of the imprinter for aready-toimprint operation, the platen roller 22 or its shaft 23 willengage the angled bar 42 to rock the arm 29 in a counterclockwisedirection about pivot member 31 and thus displace the lower end 41 ofsensor screw 39 from the upper surface of anvil 14, allowing a printingplate 25 and document 24 to be readily positioned therebetween upon thethe anvil 14. Simultaneously, with the rocking of arm 29,

spacer 34 will be raised to its uppermost vertical position,

as shown in FIGURE 3, due to its linkage with arm 29. As the platenroller is thereafter directed in the X direction to accomplish animprint, the arm 29 will then rotate in the clockwise direction, due tothe weight of spacer 34, sensor screw 39 and unbalanced arm 29, untilthe flat surface 41 of sensor screw 39 abuts the document 24 overlyingthe printing plate 25 and anvil 14. The termination of the clockwiserotation of arm 29 results in the lowering of spacer 34 a distanceproportional to combined thicknesses of the document 24 and printingplate 25. As the platen roller 22 traverses the area over anvil 14, itwill then press the document, card and anvil 14 downwardly, whereby theanvil 14 will in turn slideably force wedge block 27 horizontally towardthe front side wall 37 until it abuts the spacer 34 as illustrated inFIGURE 4. The complementary angles between anvil 14-wedge block 27 andwedge block 27spacer 34, and the movement of spacer 34 relative toreference piece 31, are so designed that the vertical positioning of theanvil 14 surface (printing bed plane) during the printing action isdisplaced by an amount substantially equal to the combined thickness ofthe specific printing plate and document to be employed as sensed by thesensor screw 39, thereby providing an optimum imprint. The systemtherefor automatically regulates the printing reference gap, between theplane of the printing bed and the upper plane defined by the travel ofthe platen shaft, to compensate for varying thicknesses of printingplates and/or documents to maintain a constant and optimum printingpressure.

It will be appreciated that, if desired, the embodiment disclosed inFIGURE 1 could easily be modified to allow the device to function as abidirectional type imprinter by providing a similar sensing assembly onthe right hand side of the imprinter along the right longitudinal axisof FIGURE 1, and connecting it to compensating spacer 34. It is alsoquite apparent that the bar 42 could be eliminated whereby the sensorscrew 39 could be raised merely by insertion of a card and/or documentbetween the sensor and the anvil. Furthermore, the printing bed couldalso be designed for allowing only the document or the printing plate tolie beneath the sensor screw 39.

FIGURE illustrates a further manner of providing complementary surfacesbetween anvil 14 and wedge block 27, to achieve not only an improvedsliding factor, but also a greater vertical movement of the anvilrelative to the smaller horizontal movement of the wedge block, thusenabling a smaller cavity area within the base to be utilized.

Another embodiment of the present invention is disclosed in FIGURE 6wherein there is shown a pair of brackets 45 having curved lips fixedlyattached to base 13. The underside surfaces 46 of brackets 45 areemployed as reference points for reasons which will become apparenthereinafter. The spacer 34 is biased in a downward direction by anexpansion spring 47, and positioned directly under the spacer 34 is acommon support 50 of the terminal portions of a pair of armlike members48 and 49, the latter being respectively rockable about a pair of pivotpoints 51 and 52. The armlike members 48, 49 have mutual angle bars 53and 54 attached thereto, which bars are so positioned to engage eitherthe platen roller 22, shaft 23, or some other portion of the platen headassembly 21 only when the platen head assembly lies in itsready-to-irnprint position. Again, the pair of compression springs 43mounted on screws 44 are employed to normally maintain the wedge block27 in a biased position toward the rear of the cavity 26.

In operation, assume the platen 22 is on the extreme right hand side ofthe printing device in a ready-to-imprint position in which case anglebar 54 is acted upon to rock armlike member 49 about pivot point 52 in aclockwise direction thus lifting spacer 34 in its uppermost verticalposition against the force of expansion spring 47. The printing plate isthen inserted between the surface of anvil 14 (printing bed) and theunderside surfaces 46 of bracket 45, thereby urging the anvil 14downwardly in accordance with the thickness of the printing plate toforce wedge block 27 toward the front side wall 37. Document 24 is thenplaced over the printing plate and motion is imparted to the platen 22for moving the same toward the printing bed area at which time angle bar54 is disengaged allowing the off-center weight of armlike member 49 andforce of expansion spring 47 to rock the arm in a counterclockwisedirection enabling spacer 34 to fall between the front side wall 37 andwedge block 27 for maintaining the latter and thus anvil 14 in a fixedposition when the platen 22 is traversing the printing bed causing animprint to be formed on the document. As the platen 22 is moved to theextreme left of the printing device, angle bar 53 will be engaged toagain lift spacer 34 for compensating purposes during a subsequentprinting operation when a new document and printing plate are used.

The reference points, underside surfaces 46, are therefore utilized toregulate the plane of the printing bed (surface of anvil 14) inaccordance with the particular thickness of the printing plate to beemployed in any one printing operation. The instant embodimentillustrates the use of a compensating anvil for bidirectional printingdevices, by adjusting only for the thickness of the printing plate foruse in those instances where the document thickness remains constant. Itis noted that the instant embodiment may be preferred for those caseswhere it is desirable to have a slight increase in the printing pressureapplied when the number of documents being imprinted upon is unusuallylarge. Obviously, the embodiment shown in FIG- URE 6 could he modifiedto compensate for the combined thickness of a printing plate anddocument or for a document only.

It should be understood, of course, that the foregoing disclosurerelates to only a preferred embodiment of the invention and thatnumerous modifications or alternations may be made therein withoutdeparting from the spirit and the scope of the invention. It is desired,therefore, that only such limitations be placed on the invention as areimposed by the prior art and as set forth in the appended claims.

What is claimed:

1. In the art of printing machines of the type adapted to use portableprinting plates, a machine comprising a base, a platen, a wedge adaptedfor horizontal movement within a single path on said base, a resilientmember biasing said wedge against such a movement, adjustable spacermeans adapted for engagement with said wedge for limiting the movementof said wedge when urged against said resilient member, an anviloverlying the wedge and adapted for proportional vertical movementrelative to the base in response to the horizontal movement of saidwedge, the surface of the anvil defining a first plane adapted tosupport thereon in superimposed relation a printing plate and at least aportion of a document for pressure engagement with the platen, a shaftsupporting said platen, means providing a fixed path to guide the shaftand thus the platen over the anvil, the path of travel by the uppersurface of said shaft defining a second plane parallel to said firstplane, sensing means for physically determining the combined thicknessof a printing plate and document to be placed on the anvil relative to areference point fixed to said base, means for connecting said spacermeans with said sensing means for relative movement 20 therewith toadjust the position of the spacer means in accordance with the saidthickness sensed, the platen adapted when pressing against a documentand printing plate to force said anvil downwardly thus moving the wedgehorizontally against the resilient member until engagement is made withthe spacer means to compensate the surface level of the anvil inaccordance with the sensed thickness allowing an optimum printingpressure to be achieved.

2. In the art of printing machines according to claim 1 including meansfor elevating said sensing means from said anvil when the platen is inits initial rest position and for urging said sensing means toward saidanvil when the platen has been moved from its initial rest position.

References Cited UNITED STATES PATENTS 764,096 7/ 1904 Williams 10l4073,179,046 4/1965 Maul et al. 101--269 FOREIGN PATENTS 333,987 8/1930Great Britain.

ROBERT E. PULFREY, Primary Examiner.

F. A. WINANS, Assistant Examiner.

